#!/usr/bin/env node

let app
const fs = require('fs')
const fileType = require('../node_modules/file-type')
const readChunk = require('../node_modules/read-chunk')
const isSvg = require('../node_modules/is-svg')
const json = require('../src/apps.json')

const basePath = 'src/drivers/webextension/images/icons/'

const iconPaths = [] // Will be used to check for stray icons

for (app in json.apps) {
  ;(function(app) {
    const iconPath = json.apps[app].icon || 'default.svg'
    const path = basePath + iconPath
    const ext = iconPath.substr(iconPath.length - 4)

    iconPaths.push(iconPath)

    if (ext !== '.png' && ext !== '.svg') {
      throw (err = new Error(
        'Icon file extension specified for app "' +
          app +
          '" is not ".png" or ".svg": src/drivers/webextension/images/icons/' +
          iconPath
      ))
    }

    fs.exists(path, function(exists) {
      if (exists) {
        if (ext === '.png') {
          const buffer = fileType(readChunk.sync(path, 0, 262))

          if (buffer === null) {
            throw new Error(
              'Unknown mimetype or bad file for "' +
                app +
                '": src/drivers/webextension/images/icons/' +
                iconPath
            )
          } else if (buffer.mime !== 'image/png') {
            throw new Error(
              'Incorrect mimetype "' +
                buffer.mime +
                '" when expected PNG for app "' +
                app +
                '": src/drivers/webextension/images/icons/' +
                iconPath
            )
          }
        } else if (ext === '.svg') {
          if (!isSvg(fs.readFileSync(path))) {
            throw new Error(
              'Incorrect mimetype when expected SVG for app "' +
                app +
                '": src/drivers/webextension/images/icons/' +
                iconPath
            )
          }
        }
      } else {
        throw new Error(
          'Missing file for app "' +
            app +
            '": src/drivers/webextension/images/icons/' +
            iconPath
        )
      }
    })
  })(app)
}

// Check for stray files in icons folder
fs.readdirSync(basePath).forEach(function(file) {
  if (!fs.statSync(basePath + file).isDirectory()) {
    if (!iconPaths.includes(file)) {
      throw new Error('Stray file (no associated app): ' + basePath + file)
    }
  }
})